Multidirectional inertia-operated safety device for vehicle chairs



Sept. 1, 1953 W. R. NEAHR ET A1. 2,650,655 MULTIDIRECTIONAL INERTIA*OPERATED SAFETY DEVICE FOR VEHICLE CHAIRS Filed Nov. l5, 1950 2 Sheets-Sheet l u ATTORNEY Sept. 1, 1953 w. R. NEAHR ET A1. 2,650,655

MULTIDIRECTIONAL INERTIA-OPERATED SAFETY DEVICE FOR VEHICLE CHAIRS Filed Nov. l5, 1950 2 Sheets-Sheet 2 IN VEN TORS dita-agg Patented Sept. l, *1953 MULTIDIRECTIONAL lNERTIA-OPERATED SAFETY DEVICE FDR VEHICLE CHAIRS William R. Neahr and Robert L. Davis, Grand Rapids, Mich., assignors to American Seating Company, Grand Rapids, Mich., a corporation of New Jersey Application November 13, 1950, Serial N o. 195,186

2,434,119, issued January 6,

3 claims. l The present invention relates to safety devices and more particularly to automatic inertiaoperated reels for taking up the cable on a shoulder harness by means of which an occupant of an airplane or other vehicle is secured in his chair.

, Y The primary objects of the invention are to provide an improved inertia-actuated safety reel of the type shown in Nordmark Patents No. 1948, and No. 2,480,335, issued August 30, 1949; to provide such a reel which is multidirectionally inertia-operable tc lock the occupant in his chair in event of collision,rcrashlanding or other emergency, that is to say a reel which will automatically lock the occupant in his chair regardless of the directional impact of the vehicle against Iany eX- ternal object.

Prior safety reels of the inertia-actuated type have operated to lock an airplane pilot, or other vehicle occupant, in his chair only in the event of a head-on collision of the vehicle with some external object (including the earth). However, it sometimes happens, and more frequently with airplanes than with other vehicles, that an initial crash takes place otherwise than head-on. In such instances the chair occupant is not so likely to be thrown forward by inertia -against the instrument panel of the vehicle as in the case of a head-on crash, but it is nevertheless desirable that he be immediately locked in his seat so that he will not be thrown sidewise or forward in the vehicle in the event of a subsequent crash as when -an airplane rebounds and crashes a second and perhaps a third and a fourth time, al1 in different directions. v

The present reel is therefore constructed so as to lock by inertia under varidirectional impact of the vehicle with some external object.

An illustrative embodiment of the invention is `shown in the accompanying drawings, wherein:

Figure 1 is a side and rear perspective view of `an airplane pilots chair showing a pilot seated therein and a safety shoulder harness passing -over the pilots shoulders and downwardly in the Figure 4 is a horizontal sectional view of the same taken on line 4-4 of Figure 3;

Figure 5 is a horizontal sectional View ofthe same taken on line 5-5 of Figure 3; and

Figure 6 is -a View partly in side elevation and partly in section similar to Figure 3, and showing certain parts of the reel in their locked positions.

Referring now in detail to these drawings, the automatic inertia-locking safety reel there shown is principally enclosed Within a housing or support generally designated I here shown secured to the underside of the seat 2 of an airplane pilots chair 3 as by means of bolts 4 and nuts 5 (see Figure 3). The chair 3 is iixedly secured to a tubular vmetal frame 6 (see Figure 1) which is securely mounted in the airplane by means not shown. The chair has associated therewith the usual lapbelt 'I and a shoulder harness 8 comprising two straps secured to the front of the chair and passing over the occupants shoulders and over a cross-bar 9 of the frame' and thence downwardly in the rear of the chair, the lower ends of the straps being joined together and secured to a clevis fitting IIJ. A cable I I is secured to the clevis fitting I0 and passes downwardly through a conduit I2 on the chair 3 into operative connection with the safety reel.

The upper part of the new reel, as shown in Figure 3, is substantially identical to the reels shown in the Nordmark patents above identified, but is here secured to the underside of the chair seat instead of to the chair back as shown in Nordmark Patent No. 2,480,335. This upper part of the new reel comprises a base I3 and a casing I 4 which forms part of the housing I, and the base and the casing are secured together and to the underside of the chair seat by the bolts 4 and nuts 5. A centrally located, downwardly projecting spindle I5 is provided with an upper flange I6 thereon (see Figure 3) seated in a recess I'I in the base I3 and rigidly secured thereto by rivets IB.

A drum generally designated I9 is rotatably and longitudinally slidably mounted on the spindle I5, and one end of the cable I I is secured to the drum I9 so that the cable may be wound thereon and unwound therefrom. The drum has in its lower portion a concentric annular recess in which is disposed a coil tension spring 20 the inner end of which is secured to the spindle I5 and the outer end of which is secured to the drum I9. The coil spring 20 tends to wind the cable Il onto the drum I9 thus taking up any slack in the shoulder harness 8 and cablev II. This structure constitutes resilient means operatively connecting the harness to the support or housing I whereby the harness may normally yield to permit freedom of movement of the chair occupant.

Locking means are provided whereby under certain conditions the drum I9 is locked to the base I3 to prevent yielding of the harness 8 thus locking the chair occupant in the chair. These means comprise ratchet teeth 2I on the circular upper surface of the drum "I3 adapted toY inter'- lock with complementary ratchet teeth 22 on a circular boss 23 on the underside of the base I3 whenever the drum I9 is caused to slide upwardlyA Patent No. 2,480,335.

The novel operating parts of the present reel rare enclosed in a cylindrical casing 29 forming part of the housing I, said casing 29 depending coaxiallyk from the casing I4 and being secured 4thereto by means of screws 39. The casing 29 has a central opening therethrough the upper and'lower portions of which are enlarged to form upper and lower annular chambers 3i and 32 respectively. The middle portion of the central opening forms a verticalfslide bearing 33 in which is'sldably disposed a plunger 34 having an enlarged upper end 35 slidable within the annular upper chamber 3| and provided with a central bore 36 which slidingly embraces the lower end of the spindle I5. The extreme upper end of the plunger is flanged outwardly and bears against the drum I9said drum being provided with a cover 31` for the drums annular recess in which is disposed spring 29, and said cover forming the bearing surface against which the plunger' bears.

'-A helical-spring 38 pressing against the casing V2,9 at the lower end ofthe chamber 3l and'against the enlarged upper end 35 of the plunger 34, Vurges the drum upwardly toward ratchet engagement with the base I3 except when prevented from so doing by the restraining means hereinafter described. The upward force of the helical spring 38 when exerted on the drum I9 is greater than the downward force exerted by the double leaf spring 24-25 interposed between the drum'and the base I3.

Thelower end of plunger 34, within the lower 'chamber 32,'hais an enlarged foot 39 thereon. `IJetents 4I) having their lower ends pivotally mounted adjacent the lower walls of chamber 32, are urge'dinwardly by springs 4I confined within cavities-42 in the casing 29 by means-o1 screws 43, so that the heads 44 of said detents may engage 'the foot'39 on plunger 33. Whenfso engaged, the spring 38 is restrainedagainst exertinge-ny vforce on the drum I9 and'is thus rendered ineffective.

Multidi-rectional inertia operable control means are associated with the detents 43'for'disengaging the detents from the plunger's foot 39 upon varidirectional impact vof the vehicle with an external object. As shown in Figure 3, an annular disc 45. is secured to the bottom of the casing 29 lay-means of screws 46, saiddi'sc 45 being provided with a recess 41 in the bottom thereof.

v ber 32, and a spring 54 interposed between the collar 53 and disc 45 normally urges the stem upwardly. The upper end of the stem I has ahead 55 thereon'which is engageable with inward projectionsor lugs 56 on the detents 40 approximately midway between the upper and lower ends of the'detents.

A cocking'lever 51 pivotally mounted on lugs 58 on the exterior surface of the casing 29, ex-

' tends through a slot 59 in the casing and has its inner end provided with a yoke 60 engaging in a reduced portion 6I of the plungers middle portion 34. v

Operation Figure 2 diagrammatically illustrates various directions of impact which an airplane may make with the earth at the time of a crash. These are merely illustrative, and the present reel will operate by inertia to lock the airplane pilot in his seat regardless of the vehicles direction of impact. When the impact occurs, pendulum 48 is swung out of its normal axial'- alignment with the plunger 34 and drum I9 as indicated by dotted lines in Figure 3. The pendulum fulcrums about the point of contact between its circular upper edge 49`and the shoulder-590i the recess 4'1 in disc 45.v Such movement of the pendulum 48draws stern 5I downwardly, and the head 55 on said stem 5I presses against the lugs on detents 40 thus camming the detents outwardly and disengaging the detents heads 44 from the foot 39 of plunger 34. The plunger being thus released, it is forced upwardly bythe helicalspring vilto its position shown in Figure 6 during which upward'moveme'nt the plunger carries with it the drum I9 and the drum is thus forced into' ratchet-interlocking engagement with Athe fixedl base I3 of the reel. The cablel II is thus locked against paying out and the pilot is secured in a rearward position in his seat. The mechanism -may be manually reset for such inertia locking by means of the cocking lever 51, the outer end of which may be forced upwardly thus lowering plunger 34 against the force of spring 38 and causing the plungers foot 39 to re-engage behind the heads 44 of detents 49.

It will thus be seen that the invention provides a multidirectional inertia-operated safety reel which is operable -upon varidirectional impactA of a moving vehicle with some external object, to lock an occupant of the vehicle -in his chair and ythus minimize the danger of injury to the occupant. While but one specific embodiment of the inventionl has been herein shown and described, it will be understood that numerous -de'- tailsy may bealtered'or' omitted without departing from-the spirit ofthe invention asthe same is defined by the following claims.

We claim:

1. For usey in a vehicle vchair having a harness for the chair occupant attached to said chair, a safety inertia-operable vcontrol device 4adapted to be secured to the'freev ends of said' harness, said device comprising a drum rotatably mounted on theV vehcle'n' association" with the chair," a cable connected to the harness'and tothe'drum whereby rotation of the drum in one direction winds the cable thereon to tighten the harness and opposite rotation of the drum unwinds the cable to relax the harness, a locking member on the vehicle and a cooperative locking member on the drum, one of said locking members being fixed relative to the vehicle and the other of said locking members being movable relative to the vehicle, a` multidirectionally inertia-operable pendulum mounted on the vehicle, and means operatively connecting said pendulum to said movable locking member whereby inertiaeffected movement of the pendulum relative to the vehicle moves the movable locking member into cooperative engagement with the fixed locking member to lock the drum against rotation in the direction which unwinds the cable.

2. For use in a vehicle chair having a harness for the chair occupant attached to said chair, a safety inertia-operable control device adapted to be secured to the free ends of said harness, said device comprising a drum rotatably mounted on the vehicle in association with the chair, a cable connected to the harness and to the drum whereby rotation of the drum in one direction winds the cable thereon to tighten the harness and opposite rotation of the drum unwinds the cable to relax the harness, ratchet means on the vehicle and cooperating ratchet means on the drum, one of said ratchet means being xed relative to the vehicle and the other of said ratchet means being movable relative to the vehicle, a multidirectionally inertia-operable pendulum mounted on the vehicle, and means operatively connecting said pendulum to said movable ratchet means whereby inertia-effected movement of the pendulum relative to the vehicle moves the movable ratchet means into cooperative engagement with the fixed ratchet means to lock the drum against rotation in the direction which unwinds the cable.

3. For use in a vehicle chair having a harness for the chair occupant attached to said chair, a safety inertia-operable control device adapted to be secured to the free ends of said harness, said device comprising a drum rotatably mounted on the vehicle in association with the chair, a cable connected to the harness and to the drum whereby rotation of the drum in one direction winds the cable thereon to tighten the harness and opposite rotation of the drum unwinds the cable to relax the harness, a locking member on the vehicle and a cooperative locking member on the drum, one of said locking members being fixed relative to the vehicle and the other of said locking members being movable relative to the vehicle, a plunger slidably mounted on the vehicle and having an end thereof in engagement with said movable locking member whereby movement of the plunger toward the fixed locking member effects locking engagement of the locking members, spring means normally urging said plunger toward the fixed locking member, restraining means releasably securing said plunger in a retracted position, a multidirectionally inertia-operable pendulum mounted on the Vehicle, and means operatively connecting said pendulum to said restraining means whereby inertia-effected movement of the pendulum relative to the vehicle releases the restraining means to permit forcing of said plunger toward the xecl locking member by said spring means.

WILLIAM R. NEAHR. ROBERT L. DAVIS.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 2,223,097 Ehret Nov. 26, 1940 2,240,085 Wells Apr. 29, 1941 2,403,653 Geohegan July 9, 1946 2,433,950 Henderson Jan. 6, 1948 2,434,119 Nordmark Jan. 6, 1948 2,480,335 Nordmark Aug. 30, 1949 2,499,993 Gregg Mar. 7, 1950 2,557,313 Quilter June 19, 1951 

